To avoid dependence on unreliable sources of fuel, automotive manufacturers have investigated developing vehicle engines powered by natural gas. Unlike conventional gasoline operated fuel systems, natural gas is stored in a pressure vessel prior to use by the engine. Any failure of such a pressure vessel could produce catastrophic results.
Advantageously, a natural gas vehicle fuel system should be made failsafe. Unfortunately, neither static nor cyclic fatigue of a pressure vessel has sharply defined cutoff points. While a tank life could arbitrarily be set at, for example, fifteen years, some vessels may be used for longer, such as thirty years, or until they fail.
The present invention is directed to solving one or more of the problems discussed above in a novel and simple manner.